Automatic loading mechanism for continuously rotated chucks



March 279 1951 R. A. ASHTON AUTOMATIC LOADING MECHANISM Foa coNTNuousLYRQTATED cHucKs F'lled Nov 8, 1947 o SSS www 22mm v E n? .bb

INVENTOR.

IIII l llllllll.

Patented Mar. 27, i951 AUTOMATIC LOADING MECHANISM FOR CONTINUOUSLYROTATED CHUCKS Richard A. Ashton, Seneca Falls, N. Y., assignor toSeneca Falls Machine Company, Seneca Falls, N. Y., a corporation ofMassachusetts Application November 8, 1947, Serial No. 784,815

This invention relates to lathes, grinding machines and other machinetools in which a work piece is gripped and rotated by a collet-typechuck. In such machines, it may be desirable to rotate the work spindleand associated parts continuously, instead of stopping and starting thework spindle each time a finished Work piece is to be removed and a newwork piece is to be inserted.

It is the general object of this invention to provide an improvedloading mechanism by which a finished workpiece may be released anddischarged and a new work piece may be inserted and gripped while thework spindle is in continuous rotation. l

More specically, I provide mechanism by which the ,finished work pieceis axially pushed out of thecollet-` jaws of the driving chuck fordischargel and replacement, and by which a new work piece is axiallyreturned to gripping positionin the chuck. I also provide means by whicha suitable tail center will receive similar axial movements and willcoact in the unloading and reloading operations.

My invention-further relates to arrangement and combinations of partswhich will be hereinafter described and more particularly pointed outinithe appended claims.

A preferred form ofthe invention is shown in the drawings, in which Fig.1 is a sectional side elevation of parts of a machine tool embodying myinvention;

Figs. 2 and 3 are detail views of certain parts appearing in Fig. 1 butshowing different operative relations;

Fig. 4 is a projection of the operative paths of certain associatedcams; and

Fig. 5 is a diagram showing a typical lay-out or subdivision of themachine cycle.

Referring to Fig. 1, I have shown a chuck I having collet jaws adaptedto grip one end of a piece of work W. The chuck |0 is mounted on a workspindle I2 supported in the usual head-stock (not shown), and the colletjaws Il are connected to a tube I4 axially slidable in the spindle I2and having a collar |5 threaded on its rear end portion.

The collar I is engaged by a plurality of cam levers |6 mounted in anextension I1 of the work spindle I2. The extension |1 is clamped to aspindle sleeve 8, secured on the spindle I2 by a nut I9. A sleeve isslidable on the extensionr I1 and has innerl cam portions 2| adapted toenfgage and depress the long arms of the cam levers I6, thus forcing thecollar I5 and tube I4 to the 4 Claims. (Cl. 82-2.7)'

2 left and closing the collet jaws I on the work W.

The sleeve 20 has a peripheral groove 24 which receives a stud 25mounted in a transmitting member 26 which is slidable on a fixed shaft21. A cam roll 30 on the member 26 is positioned in a cam groove 32 in acam 33 secured to and rotatable with a shaft 35.

A live center 40 is formed at one end of a rod 4| slidable axially inthe work spindle I2. The rear end of said rod is supported inanti-friction thrust bearings 44 secured in the rear end of an arm 46,which in turn is supported by and slidable on the fixed shaft 21previously described.

A hub portion 48 of the arm 46 has a cam roll 49 positioned in a camgroove 50 formed in or associated with the cam 33 previously described.As the cam 33 rotates, the rod 4| and the live center 40 receive timedaxial movements toward and away from the work W.

A tail center is mounted in anti-friction bearings in a member 6I whichis slidable axially in the tail stock '62. An extension 65 of the member6| is slidable in a recess 66 in a member 61 which is also mounted toslide in the tail stock 62.

An air cylinder 10 is mounted at the rear of the member 61, and a piston1| in said cylinder is connected by a rod 12 to the reduced extension ofthe member 6| which carries the tail center 60. A spring 15 isinterposed between the piston 1I andthe member 61.

The member 61 is provided with rack teeth 11 engaged by a pinion 18 on across shaft 19 mounted in the tail stock 62. A second pinion on theshaft 19 engages rack teeth 82 on a slide 83 mounted in guideways in thetail stock 62 and having a cam roll 84 seated in a cam groove 85 in arotating cam 86.

Bevel gears and 9| connect the cam 86 to a drive shaft 92 which iscontinuously rotated from a motor M through a double worm and worm geardrive, indicated generally at 93. Bevel gears 94 and 95 connect thedrive shaft 92 to a cross shaft 96, which in turn is connected throughbevel gears 91 and 98 to the cam shaft 35 which controls the movementsof the collet jaws |I and lie center 40.

The air cylinder 10 receives air through a ilexible pipe |00 from a feedpipe IOI through a three-way valve |02 having an exhaust pipe |03. Thevalve |02 is connected through gears |06, |01 and |08 to the rack teeth82 on the slide 83 previously described.

The cycle of operations of the various parts is as follows: The partsare shown in running position in Fig. 1. with the work W engaged by the3 live center 40 and gripped by the collet jaws Il. and with the tailcenter 60 yieldingly held against the tail end of the work by airpressure in the cylinder 10.

The parts are held in this position during the operation of the tools onthe Work, the tool feed being controlled by a feed caml groove IIB (Fig.4). The cam grooves 32, 5i), 85 and H0 are so related that as soon asthe Work is completed, the collet jaws l I will be released, the headcenter` 40 will be advanced to push the Work. out *ofA the` collet jaws,and the supporting members'`r 6l? andi 65 and the cylinder 10 will bemoved rearward', so that the parts will then assume the positions shownin Fig. 2.

As this movement is completed, a quarter revolution of the three-Wayvalve 102 will. like wise be completed, thus connecting the pipe to thedischarge pipe |03 and relieving the pressure in the cylinder so thatthe spring 15 may withdraw the tail center 60 to the position shownIIFg. 3*.

The Work W may thenl befrernovedL and replaced?, either manually orautomatically, whereupon continuedsrotation of thel cams` will againcause air pressure to,` be applied in the cylinder toA advance the tailcenter 6|] to support. the adjacent end. of the work piecei W; The tail.center assembly will; then bei advanced by the gear' 80 and' rackill tothe position. shownain Fig. 1, thus inserting the-newwork piece in the.collet jaws l l, while-at the Sametime the engaged live center l'iWillpbeysrhifted to the left. The collet jaws H' are then closed on thenew work piece and the' tools are fed for performanceof the required*machine operations on .the workpiece.

Atypical-division of the machine cycle is shown' dagrammatically inFig.v t but' it is to be understood that this cycle may bewidely variedby using-Z dierent cam'- lay-outs to meet different operatingconditions.

Having thus'described my invention and the advantagesY thereof, I do-Ynot Wish tozbe limitedv tov the details herein disclosed, otherwise-thanas set forth in the claims; but what I' claim is:

l: Alathecomprisingza head stock, a tall stock, ahollow work-grippingchuclr-` rotatably; mounted intsaidthead stock, Work supporting meansslidable in-said hollow chuckfor centering: and gripping one end of theWork, worksupporting meansv slidable in said tail stock for centeringand grp= ping the other end of the work, positive means for sliding saidtail stock means, impositive means for sliding said tail stock meansrelative to said positive means, positive means for sliding said headstock means, and control means operatively connected to said positiveand impositive means to operate said impositive means to cause said tailstock means to engage one end of the Work and force its other end intoengagement with said` head stock means, to then operate said positivemeans tomove said head stock and tail stool: means and the work toposition said head stocl:Y means and itsL end of the work in grippingposition4 with respect to said chuck and after a work` p'eriod toreverse said control operation to cause said positive means to move thehead stock means and Work out of said chuck while gripped by said tailstock means, and thereafter to cause said impositive means te move saidtail stock means?` fromthe'v workl to release the* saline( 22 A- lathe:as: in clainrV wherein the chuck isV continuously rotatable.-

3; Alatlief as in claim 2.,. wherein means asso# ciated with the'.lchuck eilectsztimed gripping andi releasing activities ofi the chuckrelative tothe work; A n

4. A latlreas incl-annv 3, whereinrtne impositive means is both uid andspring controllecl-V i'i' its: operation;

RICHARDA, ASHTON.

EEFERENGES CITED The following references are ofrecer-'d in tlfe' Ilfeof' this patent:

UNrrED. STATES PATEPS

